Trying to trigger a problem condition found on How-To Geek I instead ran into a different issue. I wasn’t able to create a topic title in excess of 29 consecutive non-space characters, and that was great. However, I only discovered this limit after several failed attempt at editing a topic title to exceed the limitation - as opposed to creating a new topic with an excessively-long non-broken title.
When trying to submit a new topic with a too-long title, I get an ambiguous “Title is invalid” error similar to the error used for an invalid post body. Error ambiguity is another issue, however. The problem here is that, when I try to edit an existing topic to have a too-long title I don’t get any error at all - Discourse “saves” the edits, but reverts the title change with no feedback to the user at all.